1. Field of the Invention
The present invention relates generally to a variable thermostat-type air conditioning system, and more specifically to a dehumidification switch provided for the thermostat-type air conditioning system for an automotive vehicle.
2. Description of the Prior Art
As is well known, there exists a variable thermostat-type air conditioning system for an automotive vehicle having a refrigerant cooling cycle that is automatically stopped when the air conditioner output duct air temperature as detected by a temperature-sensitive element, reaches a preset passenger compartment air temperature determined by the position of a temperature adjusting lever; that is, the cooling cycle is intermittently operated or stopped so that the output duct air temperature lies within a preset temperature range.
In such an air-conditioning system, however, when the passenger compartment is warmed by heating low-temperature high-humidity outside air the warmed air supplied to the passenger compartment tends to cause the windshield glass to become obscured by condensation, particularly during the rainy season. To prevent or correct this condition, it is necessary to operate the air conditioning system as a dehumidifier. However, since the temperature adjusting lever (the passenger compartment air temperature presetting device) has already been set to an appropriate HOT position, the cooling compressor is not operated or turns off before the correct temperature is reached. Therefore, it is necessary for the vehicle operator to reset the temperature-adjusting lever, which has been previously set at an appropriate HOT position the lever is reset to the extreme COOL side on the air conditioning system panel. Then the operator resets the lever to the HOT position after dehumidification of the air and removal of the condensate.
The arrangement of the prior-art variable thermostat-type air conditioning system for an automotive vehicle is described in more detail hereinafter with reference to the attached drawings under DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS.